In a hot surface ignition system, the igniter plays a crucial role in heating up to the point where it can ignite the gas. When the voltage to the igniter has been measured and it is determined that the igniter is not lighting, the next logical step is to perform a resistance test on the igniter. This test checks the integrity of the igniter itself by measuring its electrical resistance.
If the resistance is outside of the manufacturer's specifications, it indicates that the igniter is likely faulty and not functioning properly, even if it is receiving the appropriate voltage. A reading that shows infinite resistance or an unusually low resistance would suggest that the igniter cannot perform its intended function of igniting the gas.
Conducting this resistance test is essential because it helps to confirm whether the igniter is the source of the problem before moving on to other components, such as inspecting the gas valve or adjusting the gas pressure, which might not be relevant if the igniter is defective. Hence, performing this test effectively guides the technician toward the correct diagnosis and necessary repairs or replacements.